Cavu2u

Timing off due to error in distributor installation.

Seems like that in every rebuild I've ever done, I have never got this simple step right. CHUG, PUFFTT, BANG, etc.

Engine turns over great, with good speed and no unusual noises.

My problem this time: I have been supplied with a Cyco Systems PRO STREET Harmonic Balancer. It's got a ton of marks on it. Pretty sure I'm doing it right though by using the "0" (zero) and matching that up with the big tooth "0" on the timing cover tab, while being at #1 cylinder's TDC position.

Also the distributor wires need to be right as well.

All these things I will go over again next time I go out to the car, but..

Just had to vent.

Steve

cardo0

Nice dampner. Sounds like your hoping your dampner and timing tab are still correct after the engine work u did (u didnt list or share). And hoping the distributor is installed correctly too and not 1 tooth or maybe even 180 degrees off.

Only 1 accurate way to veryfy the timing tab. Use a piston stop and degree wheel to verify #1 is TDC at exactly 0 degrees. U can mark up your dampner with enough marks to substitute for a degree wheel. But this all takes more effort than just hoping things line up. Maybe this doesnt sound polite but if u went to the trouble for a cam change or even more than that u need to get this correct before u wipe some cam lobes.

Cavu2u

Thanks Cardo0,

I did post some of my 383 build here (least I thought I did), with pictures. In particular here, is this:



The Cam Chain Set's Crankshaft Gear is one that can be installed (read "messed up" for a rookie) for a desired advanced, zero, or retarded setting. I am 100% sure I installed that gear at it's ZERO index/setting, although the photo shows the keyway may be in the Advanced setting (visual anomaly).

I do have a wheel & pointer (http://www.summitracing.com/parts/cca-4790 , http://www.summitracing.com/parts/pow-pow101501). I originally bought them to see what kind of cam was in the old engine, because it's great power had me wondering.

Good suggestion on that wheel. Guess I'll remove the pulleys and install it to see what I've got.

And don't worry about politeness. I'm beyond that.

Steve

cardo0

The important effort here is to get the dist installed such that the rotor points to #1 plug wire when #1 is at TDC. U want to start the engine with 'bout 10 degrees of advance so u can take the engine right to 2000 RPM for 20 min to break in the cam. FYI any slow/low rpm before the cam is broken in can wipe the lobes and destroy the cam. To ensure the rotor is pointing at #1 plug wire on the cap once the dist is dropped in (while the dampner shows 0 degrees) i like to use a long straight edge to extend the line from the rotors center electrode out along/past the rotor tip and place a mark with tape on the fender on this extended line. Next i put the dist cap back on and use my straight edge between the center electode (where the coil wire plugs in) and the tape mark on the fender. If the #1 cyl cap terminal lies in that line then the dist is installed correctly for TDC on #1 cyl - if off by like 13 degrees u are off at least one tooth. I cant recall how many degrees per tooth but once u have your distributor out u can count the number of teeth and divide 360 by that number of teeth to give u the amount of change per tooth.

The easiest way to verify your at TDC on #1 is with the dampner 0 mark will be at 0 on the timing tab but the both rocker arms show the #1 vlvs are closed while #6 vlvs are open and u can see #6 rockers holding the #6 vlvs open in overlap. Problem with R&R the timing cover let alone new parts like timing set and dampner is the the timing tab on the timing set cover no longer has and accurate position for #1 cyl.

In your situation it would be prefered to verify/reset the timing tab for the dampner mark. U could possible just use what u have now on the dampber and tab as is just to set your 10 degrees initial advance to break in the cam - but its more than likey off somewhat. If u want to correct the timing tab sometime then u need a piston stop and a degree wheel (or the dampner correctly marked in degrees). U get #1 cyl near TDC and install the piston stop. Turn the crank slowing and let the piston stop do it job stopping the piston (easy here u dont want to put a hole in the piston). Note the degrees on the wheel or dampner. Next turn the crank all around the other way and again slowly approach the piston stop. Whe the crank stops turning mark/record the degrees on the wheel/dampner. Find the difference in degrees between the 2 piston stopped positions (the small angle in between not the full reverse to rotation u used to reverse the crank direction) And divide by 2. This result is when #1 is at TDC and the dampner mark for 0 degrees should match the 0 degree mark on the timing tab.

Sorry for the late reply but i was on the road yesterday. Well i hope this helps. Good luck Steve.


BTW the cam advance with those sproket marks does not affect the dampner/timing tab marks and not to worry where that sprocket was left.

Cavu2u

Anything wrong with this presentation?

Steve

Jeff_Keryk

I have a simple, fool-proof process. Have someone click key to crank engine while you hold finger over #1. You will feel compression. Stop anywhere from 6 to 10* BTDC. Stab distributer with rotor pointing towards #1 post. Install spark plug and hook up timing light. SLOWLY rotate distributer; when light flashes tighten down distributer. Verify firing order, prime carb and fire that bad-boy up. This is a 10 to 15 minute procedure with 2 people.
Anyways it works for me.

Cavu2u

Thanks Jeff,

Another good way to do it.

What I gleaned from that video;
If the distributor's rotor doesn't point to the #1 spark tower after installing the distributor at #1 cylinder's TDC @ firing stroke, get a long straight-slot screwdriver, fit it down into the oil pump's distributor drive slot, AND MOVE IT so when the distributor is inserted, IT DOES POINT to #1 spark plug tower.

Can't wait to get out there this morning and proceed.

Steve

Cavu2u

Good FYI Cardo0! Had no idea about that.
Will be sure to check the tranny fluid level before proceeding with the 20 minute long run.

Steve

Jeff_Keryk

Oh yeah, remember to have ignition on when moving distributer. Works much better...
And big screwdrivers are almost as handy as big hammers.

redman76

I've heard of people breaking in cams with a drive but it would be near impossible to maintain 2000 RPM. Best to put in park/neutral and run up to 2000 RPM while sitting in the driveway. As Cardo pointed out, it's the low RPMs that will kill the cam.

My Voodoo cam and a slightly different break-in procedure, but basically the same . . . I followed cam manufacturer's procedure.

Cavu2u

Folks,

Now that I discovered the trick (adjusting the position of the oil pump shaft) of Distributor installation, life is good. Real good!
In other words, that motor fired right up. Sounds awesome.
But before break-in procedure, thought I'd better put a timing light to it (which I left at home ), so the break-in will occur Wednesday. Maybe tomorrow. We'll see.

I do appreciate all the help you guys have lent me. Thank you! A bunch of smart cookies, and nice about it, to be sure.



Steve

Cavu2u

By the way; Oil Pressure Gauge is pegged out (+70 PSI) at idle. 74 degrees F outside. Is this anything to worry about?

This is the oil in there now;
http://www.summitracing.com/parts/luc-10631-1

I also installed a new Melling High Volume Oil Pump.

What is the greatest worry with High Oil Pressure anyway?

Thanks.
Steve